Originally Posted by oldultrarunner .
You can't do that with Dura Ace 10 speed. It's a compact crank and they don't even sell a crankset with a 50/36. And as for a rear cassette change, the biggest cassette you can get in DA is a 12-28 (or 11-28). [COLOR= #ff0000]You can't get anything higher than that[/COLOR]. This is top of line drivetrain here, not Sugino where you can swap out chainrings and make adjustments to get it to work.
Well, pardon me!?!
While I presume you are referring to my
Campagnolo Record crankset as a
Sugino crankset, there is no reason that you cannot replace the chainrings on your "top of the line" Shimano crankset with either different Shimano Dura Ace chainrings or with chainrings made by someone else.
- I believe that Sugino is still the preferred choice of non-sponsored Track riders
- as alienator has already noted, Sugino makes excellent cranksets
LEKTION EINS. The inner chainring on-or-for a Double crankset is not ramped. So, as far as replacing the inner chainring, the
only thing(s) a person truly needs to be concerned with is the BCD + the cosmetics, with the latter being a trivial matter.
Rather than spend several hundred dollars to buy a hypothetical ([COLOR= #808080]regardless of whether or not it is available[/COLOR]) 50/36 DA crankset, you would simply buy a 36t
110BCD chainring and install it in place of the existing 34t 110BCD chainring.
OR, were you planning to replace the entire crankset when you wore out the crankset's 34t (or, 50t) chainring?!?
LEKTION ZWEI. While I 'love' Shimano components and I have the highest regards for their engineers ([COLOR= #808080]okay, their mechanical shifters continue to leave something to be desired, IMO, but the deficiency has resulted in 20+ years of R&D which has benefitted the cycling world through the ramping-and/or-pinning found in their-and-other drivetrains[/COLOR]), but their marketing department is suspect, IMO.
- A dozen years ago, I was told that you couldn't mix any Shimano components which were not labeled with the same Group name. Well, through necessity, I figured it was worth experimenting with my Ultegra 6500 shifters + an XTR rear derailleur + an XTR cassette -- at the time, it was an unheard of combination ... not so much so, now.
Even YOU can substitute an [COLOR= #ff0000]11-32[/COLOR], 10-speed Shimano XTR cassette for your 12-28 cassette. While dated-by-comparison, here's a 9-speed
12-34 XTR cassette + DA rear derailleur ([COLOR= #808080]the
11t upper pulley wheel was replaced with a
10t pulley wheel[/COLOR]):
It's true that the above combination isn't on a fancy-schmancy "new Seven custom Ti/carbon road bike" ... but, I have found that frames with an off-the-peg geometry suit me:
I suppose that
my Colnago C40 frameset didn't cost as much as your "custom" Seven frameset may have cost ... or, maybe it did. Regardless, that's a 2001 frameset whose 2011 equivalent would probably cost more ([COLOR= #808080]but, which I probably wouldn't buy, now[/COLOR]).
I've changed the components on my C40 over the years ... only the Campagnolo Skeleton brake calipers & Shimano DA rear derailleur were chosen for cosmetic reasons over the components they replaced.
LEKTION DREI. Now, if you were to do some simple arithmetic, you would realize that a 34t chainring + 28t largest cog is the SAME AS a 39t chainring + 32.11t cog ([COLOR= #808080]okay, there's NO 32.11t cog, but a 32t is certain numerically close[/COLOR]).
Further, a 36t chainring + a 29.647t cog ([COLOR= #808080]oops, there's another impossible cog![/COLOR]) is equal to a 34t chainring + 28t cog, and vice-versa.
FYI. I generally ride on mountain roads, with my preference being the roadway which was formerly known as "South 14" -- the altitude ranges from 6500 to 9000 feet. The popular roadway to "The Crest" reaches 11,000+ feet & [COLOR= #000000]I'll admit that is too much climbing for me.[/COLOR]
Here is one of my in-city ("Flatlander") bikes as it was originally set up:
Since taking the picture, I made cosmetic changes which involved replacing the seatpost with a Campagnolo seatpost AND the pictured [COLOR= #0000ff]
Shimano DA 7700 [/COLOR]crankset & 50t FSA chainring with a 5-arm Campagnolo Chorus crankset + 50t Gebhardt chainring.
LEKTION VIER. I 'love' Shimano components. I have both Dura Ace & Ultegra components, and while there is weight difference, as far as I am concerned the difference is mostly cosmetics & cost ...
Regardless, a knowledgeable weight-weenie would opt for Campagnolo components over Shimano, so to argue that Dura Ace components were chosen because they weigh less is a hollow rationale for the choice of DA over Ultegra.
LEKTION FÃœNF. If you are patient, you can probably buy a NOS Shimano 7703 crankset on eBay. If you are not patient, then you can probably buy a NOS Shimano 7700 crankset and then install a TRIPLIZER inner chainring ([COLOR= #808080]available at
Harris Cyclery, etc.[/COLOR]) + any "standard" ([COLOR= #808080]74BCD[/COLOR])
Granny chainring rather than dealing with the proprietary 7703 middle-and-granny chainrings.
- I know someone in Santa Fe who set up a Triplizer with a 22t Granny + Shimano 7703 shifters.
LEKTION SECHS. I found that a 112.5mm XTR BB is suitable for any Octalink Road Double + any Octalink Road Triple crankset -- specifically, I used the 112.5mm XTR BB with an Ultegra Triple crankset.
- Depending on how the stays are shaped, the shorter, 112.5mm spindle may not work with an aluminum frame.
While the chainline with a 112.5mm XTR BB isn't as good as with a 109.5mm Octalink BB, it is certainly better than with a 118mm Octalink BB.
While the XTR BB requires a 2.5mm BB spacer (or, equivalent), I found that the XTR spindle will fit in the non-cartridge DA Octalink BB cups.
---
YOU have many options ...
Some of your options will cost more money than others ...
OR, you can ignore all the suggestions given to you by various Forum members & you can continue to complain about how your LBS set up your "custom" bike ([COLOR= #808080]or, did you assemble it?[/COLOR]) OR you can lament your inability to cross chain the small-small combinations without the chain grinding against the outer chainring.